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homer.py

@@ -907,6 +907,9 @@ def run_check_default(connection):
     return ok
 
 def run_check_mime(connection, accept="application/dns-message", content_type="application/dns-message"):
+    # change the MIME value and see what happens
+    # based on the RFC only application/dns-message must be supported, any
+    # other MIME type can be also supported, but nothing is said on that
     if dot:
         return True
     ok = True
@@ -935,6 +938,10 @@ def run_check_mime(connection, accept="application/dns-message", content_type="a
     return ok
 
 def run_check_trunc(connection):
+    # send truncated DNS request to the server and expect a HTTP return code
+    # either equal to 200 or in the 400 range
+    # in case the server answers with 200, look for a FORMERR error in the DNS
+    # response
     ok = True
     test_name = 'Test truncated data'
     if verbose:
@@ -970,7 +977,11 @@ def run_check_trunc(connection):
     else:
         if dot:
             ok = False
-        else: # a 400 response's status is acceptable
+        else: # only a 400 range HTTP code is acceptable
+              # if we send garbage to the server, it seems reasonable that it
+              # does not fail, which means we don't accept a 500 range HTTP
+              # error code (even so it means the server failed to process the
+              # input data)
             ok = (request.rcode >= 400 and request.rcode < 500)
     print_result(connection, request, prefix=test_name, display_err=not ok)
     if verbose: